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61.
目的:探讨术前量化训练方法对腰椎间盘突出患者术后锻炼依从性及康复效果的影响。方法:将84 例腰椎间盘突出患者随 机分为观察组及对照组各42 例,对照组围手术期间实施常规性护理,观察组围手术期间实施术前量化训练,对比分析两组患者 负性情绪、术后锻炼依从性及康复情况。结果:观察组干预后汉密尔顿焦虑量表(HAMA)评分、汉密尔顿抑郁量表(HAMD)评分 低于对照组(P<0.05)。观察组术后锻炼依从率、满意率高于对照组(P<0.05),而并发症发生率低于对照组(P<0.05)。观察组术后疼 痛评分低于对照组(P<0.05),观察组术后下床活动时间及平均住院时间短于对照组(P<0.05)。结论:对腰椎间盘突出患者术前进 行适应手术训练可有效改善患者负性情绪,提高患者术后锻炼依从性,有利于患者术后康复,提高患者康复效果。  相似文献   
62.
The molecular mechanisms by which chronic hypoxia, whether constant (CCH) or intermittent (CIH), alters the heart rhythm are still under debate. Expression level, control, maturational profile and intercoordination of 54 genes encoding heart rhythm determinants (HRDs) were analyzed in 36 mice subjected for 1, 2 or 4 weeks of their early life to normal atmospheric conditions or to CCH or CIH. Our analysis revealed a complex network of genes encoding various heart rate, inotropy and development controllers, receptors, ion channels and transporters, ankyrins, epigenetic modulators and intercalated disc components (adherens, cadherins, catenins, desmosomal, gap and tight junction proteins). The network is remodeled during maturation and substantially and differently altered by CIH and CCH. Gene Prominence Analysis that ranks the genes according to their expression stability and networking within functional gene webs, confirmed the HRD status of certain epigenetic modulators and components of the intercalated discs not yet associated with arrhythmia.  相似文献   
63.
The effect of calcium-sensing receptor (CaR) agonists on frog gustatory responses was studied using glossopharyngeal nerve recording and whole-cell patch-clamp recording of isolated taste disc cells. Calcimimetic NPS R-467 dissolved in normal saline solution elicited a large transient response in the nerve. The less active enantiomer of the compound, NPS S-467 induced only a small neural response. The EC50 for NPS R-467 was about 20 μM. Cross-adaptation experiments were performed to examine the effect of 30 μM NPS R-467 and 100 μM quinine on the gustatory neural response. The magnitude of the R-467-induced response after adaptation to quinine was approximately equal to that after adaptation to normal saline solution, indicating that the receptor site for NPS R-467 is different from the site for quinine. NPS R-467 (100 μM) also induced an inward current accompanied with conductance increase and large depolarization in two (13%) of 15 rod cells, and a sustained decrease in outward current and small depolarization in six (40%) other rod cells. NPS S-467 (100 μM) induced a sustained decrease in outward current and depolarization in five (50%) of 10 rod cells. Another calcimimetic cinacalcet (100 μM) induced an inward current accompanied with conductance increase in three (27%) of 11 rod cells. The results suggest that NPS R-467 induces neural responses through cell responses unrelated to a resting K+ conductance decrease.  相似文献   
64.
65.
Phenotypic plasticity is a hallmark of the caste systems of social insects, expressed in their life history and morphological traits. These are best studied in bees. In their co-evolution with angiosperm plants, the females of corbiculate bees have acquired a specialized structure on their hind legs for collecting pollen. In the highly eusocial bees (Apini and Meliponini), this structure is however only present in workers and absent in queens. By means of histological sections and cell proliferation analysis we followed the developmental dynamics of the hind legs of queens and workers in the fourth and fifth larval instars. In parallel, we generated subtractive cDNA libraries for hind leg discs of queen and worker larvae by means of a Representational Difference Analysis (RDA). From the total of 135 unique sequences we selected 19 for RT-qPCR analysis, where six of these were confirmed as differing significantly in their expression between the two castes in the larval spinning stage. The development of complex structures such as the bees’ hind legs, requires diverse patterning mechanisms and signaling modules, as indicated by the set of differentially expressed genes related with cell adhesion and signaling pathways.  相似文献   
66.
Introduction: Abnormal biomechanics plays a role in intervertebral disc degeneration. Adipose-derived stromal cells (ADSCs) have been implicated in disc integrity; however, their role in the setting of mechanical stimuli upon the disc''s nucleus pulposus (NP) remains unknown. As such, the present study aimed to evaluate the influence of ADSCs upon NP cells in compressive load culture.Methods: Human NP cells were cultured in compressive load at 3.0MPa for 48 hours with or without ADSCs co-culture (the ratio was 50:50). We used flow cytometry, live/dead staining and scanning electron microscopy (SEM) to evaluate cell death, and determined the expression of specific apoptotic pathways by characterizing the expression of activated caspases-3, -8 and -9. We further used real-time (RT-) PCR and immunostaining to determine the expression of the extracellular matrix (ECM), mediators of matrix degradation (e.g. MMPs, TIMPs and ADAMTSs), pro-inflammatory factors and NP cell phenotype markers.Results: ADSCs inhibited human NP cell apoptosis via suppression of activated caspase-9 and caspase-3. Furthermore, ADSCs protected NP cells from the degradative effects of compressive load by significantly up-regulating the expression of ECM genes (SOX9, COL2A1 and ACAN), tissue inhibitors of metalloproteinases (TIMPs) genes (TIMP-1 and TIMP-2) and cytokeratin 8 (CK8) protein expression. Alternatively, ADSCs showed protective effect by inhibiting compressive load mediated increase of matrix metalloproteinases (MMPs; MMP-3 and MMP-13), disintegrin and metalloproteinase with thrombospondin motifs (ADAMTSs; ADAMTS-1 and 5), and pro-inflammatory factors (IL-1beta, IL-6, TGF-beta1 and TNF-alpha).Conclusions: Our study is the first in vitro study assessing the impact of ADSCs on NP cells in an un-physiological mechanical stimulation culture environment. Our study noted that ADSCs protect compressive load induced NP cell death and degradation by inhibition of activated caspase-9 and -3 activity; regulating ECM and modulator genes, suppressing pro-inflammatory factors and preserving CK8. Consequently, the protective impact of ADSCs found in this study provides an essential understanding and expands our knowledge as to the utility of ADSCs therapy for intervertebral disc regeneration.  相似文献   
67.
Cells are subjected to static tension of different magnitudes when cultured on substrates with different stiffnesses. It has long been recognized that mechanical stress is an important modulator of the intervertebral disc degeneration. Here we studied the influence of substrate stiffness on cell morphology, apoptosis and extracellular matrix (ECM) metabolism of the rat annulus fibrosus (AF) cells which are known to be mechanosensitive cells. Polyacrylamide gel substrates with three different stiffnesses were prepared by varying the concentration of acrylamide and bisacrylamide, and the elastic modulus of the different gel substrates were measured with atomic force microscopy (AFM). First-passage rat annular cells were cultured on soft, intermediate, rigid substrates or plastics for 24 or 48 h. The percentages of apoptotic cells were detected by flow cytometry and caspase-3 activity, and morphologic changes were visualized by Hoechst 33258 staining and F-actin staining. In addition, the expression of ECM genes (Col1α1, Col2α1, aggrecan, MMP-3, MMP-13 and ADAMTS-5) were analyzed by RT-PCR. The three different substrates had elastic moduli varying between 1 ± 0.23 kPa (soft, 5% gel with 0.06% bis), 32 ± 2.89 kPa (intermediate, 10% gel with 0.13% bis) and 63 ± 3.45 kPa (rigid, 10% gel with 0.26% bis) with a thickness about 60-70 μm. Most of the rat AF cells appeared small and rounded, and lost most of their stress fibers when cultured on soft substrate. There was a significant increase in the percentage of apoptotic cells in the rat AF cells cultured on soft and intermediate substrates relative to those on plastic surface, with a parallel decrease in the area of cell spreading and nucleus. The AF cells grown on intermediate or rigid substrate had reduced expression of Col1α1, Col2α1 and aggrecan and enhanced expression of MMP-3, MMP-13, and ADAMTS-5 at 24 h or 48 h, respectively, relative to those cultured on plastic surface. Conversely, we observed an up-regulation of Col2α1 and aggrecan and no change in the gene expression of MMP-3, MMP-13, and ADAMTS-5 in AF cells on soft substrates. Rat AF cells are sensitive to substrate stiffness which can regulate the morphology, growth, apoptosis and ECM metabolism of rat AF cells, thus indicating the importance of substrate choice for cell transplantation and regeneration for the treatment of disc degeneration using tissue-engineering technique.  相似文献   
68.
Aims: To assess antibiotic resistance in airborne bacteria associated with coarse particulate matter (PM10) in an urban area, with specific considerations about the Staphylococcus genus. Methods and Results: Disc diffusion test was performed on 243 microbial strains, isolated from PM10 in winter and summer and belonging to families Pseudomonadaceae and Enterobacteriaceae and genera Acinetobacter, Enterococcus and Staphylococcus. Staphylococci resistances were the most heterogeneous, being distributed among almost all tested antibiotics. Staphylococcus isolates resistant to some selected antibiotics were further investigated for the presence of the corresponding genetic determinants. Only tetK, which mediates the tetracycline resistance through the action of an efflux protein, was found in almost all resistant isolates. Conclusions: The lack of specific genetic determinants makes their transmission among staphylococci less likely. This may reduce the theoretical risk associated with the inhalation of airborne micro‐organisms. Significance and Impact of Study: Although the spreading of antibiotic resistant micro‐organisms is of particular concern in clinical settings, the origin of antibiotic resistance genes can be traced in natural environments. As behaviour, viability and transport of bacteria in the atmospheric compartment suffer from a lack of information, the evaluation of the actual risk posed by airborne micro‐organisms to human health is still challenging.  相似文献   
69.
腰椎间盘突出症260例临床分析   总被引:1,自引:1,他引:0       下载免费PDF全文
目的:总结腰椎间盘突出症的临床特点及诊治要点。方法:回顾性分析260例腰椎间盘突出症手术患者的临床资料。结果:直腿抬高与影像学检查结果符合率为100%,治疗优良率达88.08%,有效率100%。结论:腰、下肢和臀部疼痛、下肢麻木、体位改变、运动障碍、感觉障碍、肌萎缩都是腰椎间盘突出症的主要临床表现;直腿抬高试验高试验可作为早期诊断的重要参考指标,要要根据惠者体征、病程等具体情况选择适合的最佳治法。  相似文献   
70.
A possible role for cAMP in the mechanism of ecdysteroid induction of morphogenesis in imaginal discs of Drosophila melanogaster was explored in a variety of experiments. Neither cAMP, supplied externally, nor theophylline at concentrations which increase internal cAMP levels 2–3 fold will substitute for the hormone in the induction of morphogenesis. Hormone action in imaginal discs is neither enhanced nor repressed by externally supplied cAMP or theophylline. Internal cAMP levels in discs, determined by kinase binding assays, are not altered by juvenile hormone or 20-hydroxy-ecdysone under incubation conditions which permit ecdysteroid stimulation of RNA synthesis and induction of morphogenesis. Adenylate cyclase activity in disc extracts is not stimulated or depressed by 20-hydroxy-ecdysone or juvenile hormone, but is stimulated by NaF. These findings suggest that ecdysteroid action in imaginal discs does not involve changes in the internal concentration or metabolism of cAMP.  相似文献   
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